Establishing an invar leveling calibration system |
| |
| Authors: | Chun‐Sung Chen Chien‐Ting Wu Ming‐Wei Chang Wei‐Chen Chang |
| |
| Affiliation: | 1. Graduate School , Ching Yun University , Jhongli 320, Taiwan, R.O.C. Phone: 886–3–4381196 ext. 5800 Fax: 886–3–4381196 ext. 5800 E-mail: ccs@cyu.edu.tw;2. Department of Civil Engineering , National Chiao Tung University , Hsinchu, Taiwan 300, R.O.C.;3. National Measurement Laboratory , Industrial Technology Research Institute , Hsinchu, Taiwan 300, R.O.C. |
| |
| Abstract: | Abstract Precise height systems are widely utilized in civil engineering projects such as high‐speed railroads, and highways and bridge construction. However, highly precise height data is obtained using precise leveling. An extremely precise invar leveling rod is necessary for obtaining precise results. In this study, an automatic calibration system for invar leveling has been established by the National Measurement Laboratory (NML). The content belongs to the long scales calibration system of D17 of the NML. This system utilizes a steady frequency laser interferometer, a CCD microscopic monitor, and a precise moving mechanism. With this system, an invar rod and a mark invar leveling rod are applied to estimate uncertainty with a 95% confidence level. Uncertainty results are 22 μm and 21 μm for the invar leveling rods and mark invar leveling rods, respectively. |
| |
| Keywords: | invar leveling rods calibration system |
|
|
